Changeset 10576

From Michael Platings, I have removed Target::normalize() as calling it was incorrect - the interpolation is already done in such a way that the Target's value is always normalized.
Finally, I have fixed TemplateTarget?<osg::Quat>::lerp() as it was giving incorrect results when interpolating between some small rotations.
From Cedric Pinson, i renamed the method in channel to be more general. Adjusted the CubicBezier? key constructor to use a single value as input.